热处理工艺对TC8M-1钛合金组织和性能的影响

Effect of heat treatment process on microstructure and properties ofTC8M-1 titanium alloy

摘要:

TC8M-1钛合金是新近研制的最高使用温度达450 °C的热强型、长寿命高温钛合金。通过对该合金进行不同温度的固溶和时效处理,研究热处理工艺对合金显微组织和力学性能的影响。结果表明：随着固溶温度的升高,合金中等轴初生α相含量逐渐减少,β转变组织进一步粗化,合金由等轴组织转变为双态组织,合金的室温强度呈下降趋势；随着时效温度的升高,合金中等轴初生α相含量无变化,合金的室温拉伸性能稍有下降,而塑性略微增加。经920 °C/2h,AC+580 °C/1h,AC热处理后,可使合金获得较好的强度–塑性的匹配。

Abstract:

TC8M-1 titanium alloy was the newly developed hot strength and long life high temperature titanium alloy, which the highest serviceability temperature can be reached at 450 °C. The effect of heat treatment process on microstructure and mechanical properties of TC8M-1 titanium alloy was researched by using solution and aging treatment at different temperatures. The results show that the content of equiaxed primary α phase decreases gradually and the transformed β structure becomes coarse with the increasing of solution temperature. Meanwhile, the equiaxed microstructure transforms into duplex microstructure. Therefore, the room temperature strength presents the decrease trend. However, the content of equiaxed primary α phase changes little with the increasing of aging temperature. The stretch strength at room temperature drops a little, but the ductility increases slightly. After heat treatment at 920 °C/2h, AC+580 °C/1h, AC, the TC8M-1 titanium alloy can be obtain the optimum combination of strength with plasticity.